Improvement



UNITED STATES PATENT OEEIcE.

JOHN It. ARMSTRONG, OF IIENDALLVILLE, INDIANA.

EMPROVEVIENT EN STANl-NGINS.

Specification forming part of Letters Patent No. 32,039, dated April 1G, 1861.

To all whom it may concern:

Be it known that I, JOHN R. ARMSTRONG, ot' Kendallville, in the countyof Noble and State of Indiana, have invented a new and useful Improvement in Steam-Engines; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specieation, in which- Figures l and 2 are elevations at right angles to each other of an engine constructed according to my invention, Fig. l being in section. Fig. 3' is a horizontal section of the cylinder.

Similar letters of reference indicate corresponding part-s in the several gures.

To enable others skilled in the art to apply my invention 'to practice, I will proceed to describe it with reference to the drawings.

B is the bed-plate of the engine.

A a is the cylinder, of oblong quadrangular forni in its transverse section, having three sides of its body made ol' a single casting, A,

Vand the fourth of a plate, a, bolted to A by bolts b b. The interior faces of the sides of this cylinder are planed so that they are perfectly parallel in a longitudinal direction.

v C is the movable head or cover ofthe cylinder provided with two stuiii ng-boxes,cc, for the two piston-rods d d, which are attached rigidly to the piston D, which is fitted to the cylinder aiidinay be packed in any suitable manner. The pistonrods are arranged one near each of the two narrower sides ofthe cylinder and piston, and both iu a plane parallel with the wider sides thereof and midway between the latter sides, and have. rigidly secured to them the slotted cross head E.

F is the crankshaft arranged at right angles lo the wider sides of the cylinder and piston and to the cross-head E, in bearings on stand- -aids G- G, bolted to the bed-plate. i

I-I is a wristplate secured to the shaft Fand carrying the crank-wrist e, which is iitted with a roller, f, to work in the slot g of the crosshead.

h is an eccentric-wrist carried by the crankwrist e for the purpose of working the slide valve, the said valve being arranged in a chest, J, attached to the cylinder, and the connection of its stern with the wrist 7LI being made by a rod, t, which gives the valve the neces sary movement to admit steam to the cylinderL above and below the piston alternately, thereby causing the piston, piston-rods, Vand crosshead to have areeiproeating rectilinear motion, which is caused by the direct action of thecross-head upon the crank-Wrist to produce a revolution of the crank-wrist and a rotary motion of the shaft.

I prefer to niake the wider sides of the cylinder and piston of a width about Vequal to twice that of the narrower sides, in order to admit of the piston-rods d d being arranged sufciently near to the ends of the slotted crosshead to give stability to the whole of the piston-connections and to dispense with the necessity of any other guides for the piston-rods than the stuffing-boxes e c. By permitting the rods d d to be set so far apart the oblong form of the cylinder and piston enables the slotted cross-head connections, which is the simplest form of crank-connection that can be made in steam-engines with stationary cylinders, to be made sufficiently unyielding without making the cylinder of such enormous area in proportion to its stroke as is necessary to obtain this result in engines with circular cylinders. Be sides this advantage of the oblong cylinder, its quadrangular form enables it to be cast without cores and in two or more pieces, thereby obviating the common occurrence ot' losing cylinders by blowing, and greatly reducing the expense of casting cylinders; and the planing out and bolting together of a cylinder of this kind can be effected at less expense than the boring of a cylinder of circular form.

l. do not claim of itself the invention of a lpolygonal steamengine cylinder; neither do I claim the invention of the slotted cross-head cranlcconnection; but i Vliat I claim as my invention, and desire to secure by Letters Patent, is-

The arrangement of the piston-rods d (Zand pistou D with the slotted cross-head E, wristplate H, wrists e h, valve-rod t', and oblong steam-cylinder A, all as herein shown and described, for the purposes set forth. i

JOHN R. ARMSTRONG.

Vitnesses:

EEENEZER DANIELs, WILLIAM W. HILDRETH. 

